Often, it is either desirable or necessary to obtain specimens of tissue from humans and other animals, particularly in the diagnosis and treatment of patients with cancerous tumors, premalignant conditions, and other diseases or disorders. For example, when it is discovered that suspicious conditions exist, either by means of x-ray or ultrasound imaging in various tissues of the body, a physician typically performs a biopsy to determine if the cells at the suspected site are cancerous.
A biopsy can be done either by an open or percutaneous technique. Open biopsy is an invasive procedure using a scalpel, whereby either a portion (incisional biopsy) or the entire mass (excisional biopsy) is removed. Percutaneous biopsy is usually done with a needle-like instrument through a relatively small incision, and can be performed by fine needle aspiration (FNA) or through the taking of a core biopsy sample. In FNA biopsy, individual cells or clusters of cells are obtained for cytologic examination and can be prepared such as in a Papanicolaou smear. In a core biopsy, a core or fragment of the tissue is obtained for histologic examination.
Intact tissue from the organ, lesion, or tumor is preferred by medical personnel in order to arrive at a definitive diagnosis regarding the patient's condition. In most cases only part of the tissue in question needs to be sampled. The portions of tissue extracted must be indicative of the organ, lesion, or tumor as a whole. Often, multiple tissue samples from various locations of the mass being sampled may be taken.
The percutaneous biopsy procedure can be performed utilizing various techniques and devices. An example is a method and a device that employs a biopsy needle for cutting tissue sample as described in British Patent Publication No. GB 2018601A. In the described biopsy device, living tissue is sucked into a cutting region under vacuum. The vacuum is created in the needle by employing connecting lines to a vacuum generator situated outside of a hand piece that holds the cannula. The cutting of the sample is done using a cutting mechanism that moves axially over the cannula. After sampling, the needle is withdrawn from the host and the sample is flushed out from the tip of the needle. The vacuum established in the hollow needle is regulated externally from the hand-piece.
Another biopsy mechanism is described in European Patent Publication No. EP 0890 339 A1. A biopsy needle with a cutting mechanism is integrated into a hand piece. The needle is connected via connections lines to an external vacuum generator and controls. The cutting device is moveable axially in the hollow space of the biopsy needle. A rotary movement, combined with a manual lengthwise push causes the cutting device to sample the tissue from the host. The sample is transported in the hollow channel of the needle. A similar arrangement is also shown by U.S. Pat. No. 5,526,822. In these devices, the vacuum generation mechanisms and controls are costly and tend to be provided in permanent fixtures that are separate from the disposable components. A manual biopsy device is known from German Patent No. DE 40 41 614 C1. In this device, a partial vacuum source is provided by a piston and cylinder pump. A similar partial vacuum-assisted biopsy device can be found in International Publication No. WO 96/28097, which has a syringe plunger arrangement located inside a manual device to create partial vacuum.
A vacuum-assisted biopsy device is described in U.S. Patent Publication No. 2001/0011156 A1, provides for a compactly configured hand device, in whose housing all drive elements necessary for propelling the needle of the biopsy needle arrangement are provided. However, a partial vacuum source is provided separate from the hand device, which can be connected via an appropriate supply line to the needle arrangement inside the hand device at a suitable connection location.
US Patent No. 20050203439, hereby incorporated herein by reference in its entirety, describes a biopsy device for taking tissue samples, which includes a housing, a removable element and a control panel. The removable part has a vacuum pump in the form of a syringe which is driven by a first motor and a biopsy needle which is driven by a separate motor under the control of a controller built into a permanent hand set. The needle and syringe are provided as a sterile package unit.
There is a need for improvements in biopsy devices that provide for high performance with low manufacturing cost, simplicity, reliability, and ease of use. Current devices are complex, either requiring many parts such as motors and drive components or providing low performance such as weak low penetration force, small sample size, poor sample integrity, etc. There is a need for design features that permit a biopsy device to be fully automated, yet fully disposable as well as economical, susceptible to efficient manufacture, simple, and reliable.